[Coral-List] Acropora palmata spawning

[Ilsa B Kuffner]

SPAWNING REPORT:
Location: St. John, USVI, Hawksnest Bay
Date: 8/17/03
Species: Acropora palmata
Depth: 3 to 0.5 m
Time spawning began: unknown (bundles being released when we entered the
water at 9:35 PM)
Time spawning ended: 10:00 PM (after 10 PM no bundles observed being
released, but water column and surface was thick with bundles at this time)
Estimated percentage of population spawning: unknown, but probably high
Tide: Mixed semidiurnal high-low at 8:40 PM and low-high at 12:29 AM
(8/18), so tide was slack to slightly rising, but overall trend was
dropping
Sea state: fairly choppy, 1 to 2 foot swells, wind 5 to 10 knots
State of local reefs: Hawksnest is the densest stand of A. palmata known on
St. John, approximately 1000 colonies of various size including many over
1.5 meter length across.  Disease (white pox) on approximately 5% of the
colonies, approximately 10% of colonies with Coralliophila abbreviata
(gastropod predator of Acropora spp.), approximately 15% of colonies with
Damselfish damage (chimneys and bites)
Comparison to previous years: This was the first known documentation of A.
palmata spawning in St. John

We began monitoring for spawning on Thursday, 8/14/03 from 9:30 to 11:30 PM
each day and observed nothing until last night.  We were targeting a little
too late in the evening, so it is possible that some colonies spawned on
8/16 as well, but 8/17 was a vigorous spawn and gametes were visible in the
water column until 10 PM.  We will be on site again tonight, so we are
hoping for another active night to collect and rear gametes.

Good luck to all who are monitoring the spawning in the Caribbean!

Ilsa Kuffner, US Geological Survey (USGS)
Rikki Grober-Dunsmore, USGS and University of Florida
Victor Bonito, University of Florida
Caroline Rogers, USGS


Ilsa B. Kuffner, Ph.D.
US Geological Survey
Center for Coastal and Watershed Studies
600 4th Street South
St. Petersburg, FL 33701

Tel: (727) 803-8747 x 3048
Fax: (727) 803-2030